The invention resides in an intake system of a multicylinder internal combustion engine with exhaust gas recirculation, particularly a Diesel engine, including an intake duct with a throttle valve. The intake duct is connected to an intake manifold with intake duct structures leading to the various cylinders. An exhaust gas recirculation line is connected to the intake duct downstream of the throttle valve.
It is well known that, with exhaust gas recirculation (EGR), NO.sub.x emissions can be substantially reduced in gasoline as well as in Diesel engines especially in the partial power operating range of the engines. Generally, with external EGR systems, exhaust gas is introduced into the intake duct by way of an EGR valve downstream of the throttle valve (see, for example, DE 34 25 378 A1). It has been found however that a uniform mixture of exhaust gas and intake air (air or air/fuel mixture) cannot be achieved in this way so that no uniform exhaust gas/air mixture is supplied to the various cylinders of the engine.
It is the object of the present invention to provide an intake system for a multi-cylinder internal combustion engine with exhaust gas recirculation wherein the exhaust gas is uniformly mixed with the charge air over the full engine operating range that is in every position of the throttle valve.